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Accessing Material Properties outside of Material Node
Posted Feb 28, 2013, 6:43 a.m. EST Heat Transfer & Phase Change, Materials, Parameters, Variables, & Functions Version 4.3a 1 Reply
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Hello, I'm working with variable material properties and I also need to use these material properties to further define other variables and boundary conditions.
I'm specifically working with steam and the Heat Transfer Physics interface.
by using: mat.def.Cp and material.Cp I am perfectly able to access these values outside the materials node.
HOWEVER
If i try to do the same thing for the thermal conductivity it doesn't work. I tried mat.def.k, material.k, material.kii and several other crazy possibilities!!!!
I found a way around it which was using the name of the variable in the physics interface, the one where COMSOL maps the material properties (e.g. ht.kxx)...but I am unsure as to which temperature is being used to define this k, the one from the domain tgoverning that physics? or the one I defined in the material node?
I would like to know is there is a way for calling the thermal conductivity the same way I did the others: mat.def.Cp, mat.def.rho..
etc...
Is it possible?
I'm specifically working with steam and the Heat Transfer Physics interface.
by using: mat.def.Cp and material.Cp I am perfectly able to access these values outside the materials node.
HOWEVER
If i try to do the same thing for the thermal conductivity it doesn't work. I tried mat.def.k, material.k, material.kii and several other crazy possibilities!!!!
I found a way around it which was using the name of the variable in the physics interface, the one where COMSOL maps the material properties (e.g. ht.kxx)...but I am unsure as to which temperature is being used to define this k, the one from the domain tgoverning that physics? or the one I defined in the material node?
I would like to know is there is a way for calling the thermal conductivity the same way I did the others: mat.def.Cp, mat.def.rho..
etc...
Is it possible?
1 Reply Last Post Feb 28, 2013, 7:08 a.m. EST
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Posted:
1 decade ago
Hi,
Use mat1.def.k11, mat1.def.k22, etc. for a Material node called mat1. There are a total of 9 components for a general 3D thermal conductivity tensor, mat1.def.kij, where i and j run from 1 to 3. For an isotropic thermal conductivity k, mat1.def.k11, k22, and k33 are all equal to k, and the other "off-diagonal" components are zero.
Best regards,
Magnus Ringh, COMSOL
Use mat1.def.k11, mat1.def.k22, etc. for a Material node called mat1. There are a total of 9 components for a general 3D thermal conductivity tensor, mat1.def.kij, where i and j run from 1 to 3. For an isotropic thermal conductivity k, mat1.def.k11, k22, and k33 are all equal to k, and the other "off-diagonal" components are zero.
Best regards,
Magnus Ringh, COMSOL